Pressure lubricator



May 6 1924.

L43fl49 M. E. MITCHELL PRES SURE LUBRI CATOR Filed March 8, 1922 2 Sheets-Sheet 1 May a, 1924. I 1,493,049 M. E.'MITCHEL.L v

PRES SURE LUBRI CATOR Filed March 8, 1922 2 Sheets-Sheet 2 j E. mimosa):

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Application mm name a, ma Serial no. aerate.

To all whom it my concern:

Be it blown that I, MALCOLM E. M1, a citizen of the United States, residing at San Francisco, in the county of San Francisco, State of California, have invented a new and useful Pressure Lubricator, of which the following is a specification, in such full and clear terms as will enable those skilled in the art to construct and use the same.

This invention relates'to a grease gun intended to make use of compressed air in supplying the grease cups of any type of machinery with lubricant.

It will be understood by those skilled in the art that it is common to provide some sort of high pressure gun for forcing grease into bearings. These guns usually take the form of a pump cylinder with a piston therein, the piston having a rod with a very fine thread to give the necessary pres sure when the rod is turned. Such grease guns are somewhat diflicult to'fill because of the fact that the grease entraps a quantity of airgin the cylinder and they-necessitate a considerable amount of turning of the piston rod to restore the piston to its initial position, since to produce the pressure required it is necessary to have a veryfine thread.

With the present invention any desired pressure may be attained and a given charge of grease may be ejected from the gun as rapidly as may be required, or if a high pressure is not desired the entire contents of the storage receptacle may be ejected there from into a gear case or other grease recep-- tacle by the opening of a valve on the low pressure side of the gun.

Another object of the invention is to pro-- vide the grease receptacle with a septum which will he airtight and which will not permit the escape of any grease into the space at the back of the septum, thus dispensing with the ordinary form of piston for pushing the grease out of the storage receptacle.

Another object of the invention is to provide means for maintaining'a continuous supply of grease in the high pressure chamber, thereby making the apparatus ready for operation at any moment.

Another object of the invention is to provide means whereby the operating valve will be substantially automatic in resetting itself, an unbalanced pair of valves 1.; used so that a more pressure of the th on the end of the valve will cause the grease to be expelled fromthe gun, and upon releasing the pressure on said valve the valve will be restored to its initial 0- sition and the gunreset to'deliver' anot er char e of rease therefrom.

0t er 0 jects of the invention pear as the description proceeds.-

An embodiment of the invention is shown in the accompanying drawings in which the same reference numeral is applied to the same 1portion throughout, but E am aware that t ere may he modifications thereof.

Fig. l is a side elevation-of the gun complete, and

will ap- Fig. 2 is a vertical sectional view of the opening 6 in the handle 2. The passage-' way 4 extends from a position on the outside of the handle to and terminates in the hole 6 at one side of the termination of the port 3. The passageway 5 extends from a position at the outside of the handle to and giirrginates in a smaller hole 7 in the han- A pin 8 carries the piston 9 and the smaller piston 10. These pistons are slidable in the holes 6 and 7 respectively, and' the pin 8 has a pin 11 to prevent it from being pushed out of the position it should occupy. This pin also terminates in a buttonh12 for the operator topush the pin in wit A flan ed cylinder 13 is 'bolted on the back of t e depending portion of the handle to cover the lower openings of the two ports 4 and 5, the port 4 being covered by the open front of the cylinder, while the port 5 coincides with the front opening of a port 14 formed in the walls of the cylinder 13 and extending to the hack of said cylinder.

A iston rod 15 carries a suitable piston 16 with double packing gaskets 17 and 18. These gaskets 1 and 18 are held in place by means of the two washers 19 and 20. At the other end the rod 15 is somewhat reduced as indicated at 21 and passes through a. packing at 22 in the upper portion of the front part of the grease receptacle 23. p

'lhe grease receptacle 23 is secured to the storage receptacle 1 by means of a series of screw bolts 24 and by two heavy cap screws 25. A suitable septum 26 is bolted between the two flanges of the grease receptacle and normally fits against the bottom of the receptacle 1. This septum is of any sultable material such .as leather or specially prepared fabric to cause the grease in the storage receptacle to be forced into the high pressure chamber without any oi the grease passing to the back of the septum.

The chamber 23 is closed with a screw cap 27, which screw cap carries a small plug valve 28 to permit it to have the flexible grease pipe 29 secured thereto, whenever it may be desired to use the grease at a pressure of from fifty to seventy five pounds which is the ordinary low pressure used. This cap has wings 30, 31 to permit it to be readily turned y hand.

The upper portion of the grease receptacle 23 has a chamber 32 in which the rod 21 is slidable, and there is an opening from said chamber into the grease receptacle 23, this opening being closed by means of the ball valve 33. A spring 34 holds the ball valve normally seated, and the plug 35 holds said spring in place.

The plug 35 is threaded to receive a cap screw 36 adapted to hold an L-shaped member 37 which is fastened to the end of the handle 2 to prevent the pin 8 from being blown out of place. Screws 39, d0 connect the handle'end to the member 37.

In 0 oration the flexible tube 29-wi1l be normally connected as shown in the figures. A suitable air pressure ipe will then be connected to the threaded oss 41 at the back of the grease receptacle 1, and as the valve 28 is normally closed the pressure will cause the grease to be forced up into the chamber 32. This air pressure has free access through the port 3. to the two pistons 9 and 10, but as the piston 9 is larger than the piston 10 they will normally occupy the position shown in Figure 2. When the tube 29 is connected to the lubricating cup on the machine to be lubricated, pressure-on the end of the button 12 will shift the pistons 9 and 10 so that the compressed air in the cylinder 13 will escape therefrom through the port 4, and at the same time the compressed air will pass through the port 5 into the back of said cylinder and force the piston 16 forward delivering from the gun a charge of grease under a pressure proportionate to the size of the piston 21 as related to the piston 16 and pressure used therein. As soon as the pressure on the button 12 is released the air pressure will cause it to be incense restored to the position shown in Figure 2,

which will at once restore the piston 15 and pin 21 to the position shown in Figure 2 and force a fresh supply of grease into the chamber 32.

In order to prevent any escape of air fi'om the cylinder 13, a gasket 13' 15 inserted be tween the cylinder and the handle portion 2. This gasket has a small hole at the center to receive the piston rod 15 so that the leather stands up as indicated at 15 to act as a packing for the opening through which the piston rod 15 extends.

In order to prevent the formation or a vacuum in the space surrounding the rod 21 there is a hole 21' to allow the atmosphere to have access to that chamber.

What I claim is as follows, but various modifications may be made in the construction shown in the drawings and above particularly described form, within the purview of my invention.

1. In a lubricator, a storage receptacle, :1 I

flexible partition therein, means to apply air pressure to one side of the partition to expel lubricant in the receptacle on the other side of the partition, a secondary pressure cham-v ber with which the lubricant chamber is connected, a valve to retain the lubricant in said secondary chamber, a large piston, a small piston operated thereby and means to apply the air pressure in the storage receptacle to the large piston to increase the discharge pressure of the lubricant as it is forced from the secondary chamber.

2. In a lubricator, a storage receptacle, a

flexible partition therein, means to applypressure to one side of said partition to expel the lubricant from the receptacle, a secondary pressure chamber to whichthe first receptacle is connected, a pressure raising piston in the secondary chamber, a larger piston for operating the pressure raisingpiston, a valve for operating said piston at a predetermined moment, and means to automatically supply the lubricant to the secondary chamber after each operation of the piston therein.

3. In a lubricator, a storage receptacle, a flexible partition therein, means to supply air pressure on one side of the partition, a secondary pressure chamber connected to the storage receptacle, a plunger extending into said secondary chamber, a larger piston to operate the plunger from the air pressure in the storage receptacle and means to apply the air pressure from the storage receptacle to either side of the larger piston at will.

4. In a lubricator, a storage receptacle, means to apply pressure thereto, a flexible partition against which the pressure is applied to expel the lubricant in said receptacle, a secondary pressure chamber connected therewith, a plunger therein, a larger piston connected to the plunger, means to cause the ondary chamber,

movement of said plun er from the pressure in the storage receptac e, and an automatically returned valve for causing the operation of the plunger at will.

5. In a lubricator, a storage receptacle, a flexible partition secured. in the middle of the storage receptacle and capable of being pushed into contact with either end of the storage receptacle, means to apply pressure at the back of the partition to expel the lubricant from the storage receptacle, a secmeans whereby the lubricant may be expelled from said secondary chamber, there being connecting passageways between the storage receptacle and said secondary chamber, and means to restore the operating mechanism to its initial position through the pressure in the storage receptacle at the back of the flexible partition therein.

6. In a lubricator, a storage receptacle, a flexible partition secured therein adjacent the middle of the same capable of being pushed into contact with either end of said receptacle, means to apply fluid ressure at the back of the partition to expe the lubricant from the storage receptacle, a secondary chamber into which the lubricant is forced from the storage receptacle, a piston to expel the lubricant from the secondary chamber, means to operate said the pressure at which the ubricant may be expelled from the secondar chamber, and means operatively connecte with the storage receptacle whereby the fluid pressure iston to increase be used to restore the plungertherein may position after each operation to its initial thereof.

7 In a lubricator, a storage receptacle, a secondary chamber, means whereby fluid under pressure will force lubricant'in the storage receptacle into the secondar chamber, a lunger to expel the lubricant from the secon ary chamber, a fluid operated piston to reciprocate the plunger, and a valve adapted to normally permit access of pressure to the plunger operating mechanism to retract the plunger, other means being provided to move the plun er forward at will when lubricant is to be expelled from the apparatus. Y

8. In a lubricator, a storage receptacle, a flexible partition therein, a secondary chamber into which lubricant is expelled from the storage receptacle, a check valve to prevent the return of the lubricant to the stora e receptacle, a plunger for expelling the ubricant from the secondary chamber, fluid oper ated means to increase the pressure of ex ulsion'of the lubricant from the secon ary chamber over that of the storage receptacle, and means for alternately applying pressure to opposite 'sides of the plunger 0 erating mechanism to expel lubricant from t e apparatus and to restore the plunger to its normal position at will. I

In testimony whereof I have hereunto set my hand this 24th day of February A. D.

MALCOLM E. MITCHELL.- 

